Nero Fest 2019

"Beware : my shackles fall with the heads of the condemned."

Enemy Layout

Fatal Battle 1/1	666,900 First Hassan	101,340 Failed Candidate	7,548 Failed Candidate
	717,310 First Hassan
	7,548 Failed Candidate	101,340 Failed Candidate	63,883 Failed Candidate
	101,340 Failed Candidate	7,548 Failed Candidate	63,883 Failed Candidate
		7,548 (...etc - 99 total)

[High Difficulty] Exhibition VI: At The Abyss (First Hassan) AP - 1

Drops	Assassin Monument x1
Rewards	Summon Ticket x1 Cursed Beast Gallstone x5

Boss Statistics

"The Old Man of the Mountain" - First Hassan

First Hassan
	HP	666,900
	LVL	90
	HP	717,310
	LVL	90
	Class	Assassin
	NP Bar
	NP Type	ST
	Actions	Up to 3 per turn
	Traits	Male, Humanoid, Servant, Brynhild's Beloved, Weak to Enuma Elish

Active Buff 1		Blessing of the Dead: Increase Damage Resist against all attacks. (Unremovable) First Hassan starts with 19 stacks of this buff, which are removed as he decapitates Candidates (once per turn).
Active Buff 2		Death Rate Up: Increase own Instant Death Success Rate. (Unremovable) All of First Hassan's normal attacks have an extremely high Death rate.
Effect 1		Judgement: At the start of every enemy turn, apply Target Focus (1 time) to any random Servant. Does not use a turn. Originally this always applied to the leftmost Servant, but it appears to be a random target now.
Effect 2		The Chain of Judgement: At the start of First Hassan's turn, inflict Death on one ally and apply a random effect based on the ally consumed. Does not occur if no allies are present. Does not consume one of First Hassan's turns. - (~7,548 HP): Restore 10,000 HP. - (63,883 HP): Increase Critical Rate (3 turns). - (101,340 HP): Increase ATK (3 turns) and Increase NP Gauge by 1.
Key Observation: First Hassan will not use The Chain of Judgement if he can NP.
*Key Observation: The Chain of Judgement is not* random, it will select the highest base HP candidate. If both candidates are the same mob type, it will randomly (?) target one of them.**
Effect 3		Sublimation of the Soul: At the end of the enemy's turn, if The Chain of Judgement was used this turn, removes one stack of Blessing of the Dead.
Post-Break Effect 1		Cloak of Warding: At the start of each turn after break, randomly applies one of the following: - Evade Quick: Evade all Quick attacks (1 turn). - Evade Arts: Evade all Arts attacks (1 turn). - Evade Buster: Evade all Buster attacks (1 turn). *It is possible for him to have the same type of Evasion two turns in a row.
Skill 1		Battle Continuation EX: Grants self 5000 HP Guts status for 1 time (5 turns).
Skill 2		Protection of the Faith A+++: Increases own debuff resistance (3 turns). Recovers 2500 HP. Increases own defense (1 turn). Increases own attack (3 turns).
Skill 3		Evening Bell EX: Increase own Buster effectiveness (1 turn). Decrease Death Resist for all enemies (1 turn).
NP Effect		Azrael: Deal damage to a single enemy. High chance to inflict Death to a single enemy.

Failed Hassan Candidate - Effects

First Hassan will [decapitate] and randomly kill one of the Failed Candidates each turn if there are any alive on the field when his turn starts.
Candidates, upon being decapitated, will provide First Hassan with buffs depending on the type as listed below. For each decapitation, First Hassan will also lose one of the 19 Damage Resist buffs he begins with.

63,883 Failed Candidate		Skill: Decrease NP Gain for a single enemy (3 turns).
63,883 Failed Candidate		Decapitated: Increase First Hassan's Critical Rate (3 turns).
~7,548 Failed Candidate		Skill: Decrease Critical Strength for a single enemy (3 turns).
~7,548 Failed Candidate		Decapitated: Restore 10,000 HP to First Hassan.
101,340 Failed Candidate		Skill: Apply Debuff Immune to a single enemy (1 time).
101,340 Failed Candidate		Decapitated: Increase First Hassan's ATK (3 turns) and Increase First Hassan's NP Gauge by 1.

Failed Hassan Candidates - Spawn Order

#	Letter	Type
1	A	7,548HP
2	B	101,340HP
3	C	63,883HP
4	D	101,340HP
5	E	7,548HP
6	F	63,883HP
7	G	7,548HP
8	H	101,340HP
9	I	7,548HP
10	J	101,340HP
11	K	63,883HP
12	L	63,883HP
13	M	7,548HP
14	N	63,883HP
15	O	101,340HP
16	P	101,340HP
17	Q	7,548HP
18	R	101,340HP
19	S	7,548HP
20	T	63,883HP
21	U	7,548HP
22	V	101,340HP
23	W	63,883HP
24	X	101,340HP
25	Y	7,548HP
26	Z	7,548HP
27	AA	63,883HP
28	AB	101,340HP
29	AC	7,548HP
30	AD	63,883HP
31	AE	7,548HP
32	AF	101,340HP
33	AG	7,831HP
34	AH	101,340HP
35	AI	101,340HP
36	AJ	63,883HP
37	AK	7,831HP
38	AL	101,340HP
39	AM	63,883HP
40	AN	101,340HP
41	AO	8,113HP
42	AP	63,883HP
43	AQ	101,340HP
44	AR	101,340HP
45	AS	8,113HP
46	AT	7,548HP
47	AU	63,883HP
48	AV	101,340HP
49	AW	8,113HP
50	AX	101,340HP
51	AY	63,883HP
52	AZ	63,883HP
53	BA	8,113HP
54	BB	63,883HP
55	BC	101,340HP
56	BD	63,883HP
57	BE	8,113HP
58	BF	...

Overview

WARNING: First Hassan's Behaviour has been altered to no longer Focus Target on the leftmost Servant. Welcome to our new Hard Mode! [Pending info on whether this gets fixed in the 2023 rerun]
An even more fiercesome battle awaits with the King of Hassans, who dialed up the random nature of this fight. First Hassan cannot be heavily damaged through his Special Defense buffs during the initial phase of the fights and Masters must survive First Hassan's Instant Death, high-critting onslaught while his protections wears off.
Due to First Hassan’s Discernment skill, each turn one random Servant will be the Target Focus of his first attack. Unlike on other servers, Masters thus cannot control First Hassan's NP and Instant Death potential as easily. Note that with one Hassan alive after decapitation First Hassan will act twice per turn, with his second attack thus potentially hitting any member of the team.
Activating a Taunt of your own will not redirect the initial Taunt. If First Hassan is about to NP, it will be a coinflip on who gets to die.
First Hassan has an incredibly high Instant Death chance on his normal attacks. While this is a highly RNG mechanic, Masters can mitigate this partly by picking Servants with low Death Rate and devoting their team composition around being able to recover from any Instant Death effect.
Rerun: Instant Death Immunity effects are also an available option. Skadi, Nightingale, Kijyo Koyo, and Miss Crane all have targetable / party instant death immune effects, which can help greatly mitigate the randomness of the fight.
In addition, First Hassan's NP is basically going to hit that Instant Death Chance. Masters must typically rely on Guts to be able to survive through it (in addition to the massive damage it deals).
First Hassan will power up and gain access to an incredibly high Critical Rate if Masters allow him to kill the Hassan with the middle amount of HP (63,883), and when buffed he is capable of one-shotting even enemies he is disadvantaged against. Stacking defense buffs or class advantage and planning defensive tool usage is vital in counteracting his one-shot capacity.
Regardless, expect First Hassan to do an extreme amount of damage.
While Invincibility and Evasion can help to avoid the damage of First Hassan’s Noble Phantasm or normal hits, they do not protect against Instant Death. Guts status, however, can help a Servant survive through Instant Death.
Masters should always leave a Hassan on the field for First Hassan to decapitate. Not only does this help to remove his layers of protection one by one, but not killing any Hassan candidates will reduce the amount of actions First Hassan has.
First Hassan will always follow a set order of Candidates he prefers to decapitate. The highest (base) HP enemy will be targeted first, and if there are 2 Candidates of the same kind (typically the 7k HP one), he will randomly select one of them.
A key early decision is to choose whether to kill the candidates with the most dangerous decapitation effects, or to simply leave all the candidates to their own devices.
Honestly, the fight is both a lot more predictable, and less stringent on the damage required/offensive buffs needed, if Masters just elect to only ever attack First Hassan.
Note that in this case, the small 7k HP Candidates will be able to charge their NP bar to full. This isn't a big deal. Their Charged Attack does reduce the target's Attack, which can be annoying in the final stages of the fight.
As First Hassan's Special Defense buffs are stripped, he becomes increasingly vulnerable. Masters do not need to wait for all Special Defense buffs to go away. He is already vulnerable especially to buff-stacked enemies even with a fair amount of Special Defense buffs left.
First Hassan gains a random Evasion to a card type after Breaking his first HP bar. This Evasion is entirely random, and he may well decide to evade against the same card type 3-times in a row.

Pre-release Guide

This is a battle of attrition, as First Hassan cannot be heavily damaged through his Special Defense buffs during the initial phase of the fights. Stalling the fight until his protection wears off is the most optimal way to tackle the challenge.
(Inaccurate for now!) Due to First Hassan’s Discernment skill, the Servant standing on the left-most (first slot) of the party will always take the first of attacks from First Hassan or the other Hassans. Caution that this only works for one hit or skill, so other Servants can be targeted afterwards.
First Hassan has an incredibly high Instant Death chance on his normal attacks. While this is a highly RNG mechanic, Masters can mitigate this by picking a Servant with low Death Rate to be on the left-most Servant and devote their team composition around protecting said Servant.
In addition, First Hassan's NP is basically going to hit that Instant Death Rate.
First Hassan will power up and gain access to incredibly high Critical Rate if Masters allow him to kill the Hassan with the middle amount of HP (63,883), and when buffed he is capable of one-shotting even enemies he is disadvantaged against. Stacking defense buffs and planning in advance defensive tools usage is vital in counteracting his one-shot capacity.
Regardless, expect First Hassan to do an extreme amount of damage.
While Invincibility and Evasion can help to avoid First Hassan’s Noble Phantasm or normal hits, they do not protect against Instant Death. Guts status, however, can help a Servant survive through Instant Death.
Masters should always leave a Hassan on the field for First Hassan to decapitate. Not only does this help to remove his layers of protection one by one, but not killing any Hassan candidates entirely will reduce the amount of actions First Hassan has.
First Hassan will always follow a set order of Candidates he prefers to decapitate. The highest (base) HP enemy will be targeted first, and if the two of the same candidates are on the field, he will target the one in the first enemy slot.
A key early decision is to choose whether to kill the candidates with the most dangerous decapitation effects, or to simply leave all the candidates to their own devices.
Honestly, the fight is both a lot more predictable, and less stringent on the damage required/offensive buffs needed, if Masters just elect to only ever attack First Hassan.
Note that in this case, the small 7k HP Candidates will be able to charge their NP bar to full. This isn't a big deal.
As First Hassan's Special Defense buffs are stripped, he becomes increasingly vulnerable. Masters do not need to wait for all Special Defense buffs to go away. He is already vulnerable especially to buff-stacked enemies even at 4-8 Special Defense buffs left.
First Hassan gains a random Evasion to a card type after his Breaking his first HP bar. This Evasion is entirely random, and he may well decide to evade against the same card type 3-times in a row.

Team Recommendations

The changes in targeting behaviour make this Challenge Quest a lot more difficult and especially, much more random than it already was.
Each hit from First Hassan has a chance to cause Instant Death, and an unlucky Instant Death activation can spell doom for a (long) run. As such, resetting the game before the attacking turn ends is a very common strategy for this fight.
By using a new (defensive) skill, changing targets, or using/not using an NP, a Master can alter the chain of events and "roll" a new enemy behaviour pattern. Hopefully, that new chain of events will not lead to a random Instant Death activation from First Hassan's basic attacks.
All is fair with a Summon Ticket on the line after all.
Anyway, the amount of working strategies has been heavily reduced.
The main objective is to stall First Hassan for as long as neccessary to weaken his defenses enough to allow the Main DPS to finish him off.
Once he is fully vulnerable especially, he will perish very quickly, a single DPS Servant is all that is technically required, with the rest of the team entirely dedicated to keeping First Hassan busy long enough.
There are four main stategies:

Order Change one DPS (fed with turn 1 buffs) with Divine Three-Legged Race to the sixth slot and stall for as long as possible and hope that by the time the DPS is back, First Hassan is vulnerable and can be killed in 2-3 turns.
Instead of Order Change, keep that DPS in the main team in either slot 2 or 3 and slowly wail on First Hassan - a more gradual approach.
The Super-Sustain Team: Using (NP-Upgraded) Supports such as Merlin and Jeanne d'Arc with the likes of Irisviel/BB/Tamamo to sustain throughout the complete fight and grind First Hassan down.
Stack enough Offensive buffs with Merlin/Waver on the Main DPS( such as Sanzang), Order Change them to the back and stall for 6 turns while letting 3 Tank Servant attempt to absorb First Hassan's NPs and attacks, whereupon the buffed Main DPS comes back, gets another rounds of Merlin/Waver buffs and finishes the fight within 3 turns.

Generally, a mixture of either option 1 and 3, and option 2 and 3 is used where Masters just attempt to stall for as long as possible. Option 4 is a high-RNG possible rushing strategy that is very tempting to try to circumvent the random nature of the fight.
The thing is, a stalling strategy is much more unreliable with First Hassan's attacks being completely unpredictable and shutting down many Sustain-based strategies with a random Instant Death proc.
Irisviel thus grants some immense relief by bringing in a Guts safety net no other Servant can put up as often. In a super stalling composition (2 of Merlin/Jeanne d'Arc/Tamamo + Irisviel), the team can outlast all of First Hassan protection layers without any deaths.
Throwing enough Tank Servants at First Hassan can also buy just enough time to weaken him - although this will be very heavy on the RNG and will often cause the main (offensive buffing) support to die before enough turns have been tanked.
Servants with extreme damage protection such as all Cu Chulainn Servants (especially those with Guts), Guts-based Servants such as Nero Claudius and Heracles (especially with Bond CE) remain the best options to stall First Hassan in a non-sustain composition.
In addition, High Death Resistance does help bring some more stability (and fewer resets). BB and First Hassan are great options to try and keep alive as they will not be as easily instantly killed.
Supports with extensive protections especially with Invincibility/Evasion/Other Defenses are still useful, but extremely prone to dying to random Instant Death procs (or his NP. Granting them guts via a CE or otherwise is not a bad idea. Jeanne d'Arc, Merlin, Mash, etc. can all buy valuable time overall either way.
Guts Support is also very useful to keep Servants alive, especially against First Hassan's Instant Death on NP. Irisviel, Nero Claudius (Caster) and Paracelsus are some darkhorse options for this approach.
Taunting Servants are only somewhat useful for helping to distract secondary attacks from the team, but these Servants are very prone to be hit by an Instant Death. They will also not fully prevent the first attack from First Hassan to hit a valuable support/DPS, instead giving it a 50/50 chance.
Lastly, Defensive CEs are very powerful. For Servants with no Guts, a Guts CE is highly recommend (doesn't matter which one, but Necromancy is too RNG-heavy and prevents guts skills), while Servants with a Guts ought to go for CEs like Volumen Hydrargyrum.
For full-sustain tanking, The Holy Shroud of Magdalene is very powerful to be able to live through First Hassan's normal damage. In addition, Prisma Cosmos is highly recommended for Servants like Jeanne d'Arc to get her NP up in time.
The Craft Essence - Mature Gentleman is the only Craft Essence in the game that currently grants Instant Death Resistance. Equipping this on the Servant in the First Slot is a decent way to improve their survivability - but puts that Servant at risk of dying from First Hassan's normal damage.

Picking a Damage-dealer

Ideally, only a single Main DPS is needed.
A Single Target Caster would generally be the best option thanks to the class advantage, but Berserker and Alter Ego Servants are more than capable as well.
Sanzang can really pull her weight here, being capable of launching her NP twice in succession to try and finish the final stretch in 2 turns. She is extremely compatible with an Order Change strategy.
Cu Chulainn (Alter) is also great, especially as he can stay on the field and tank additional First Hassan hits (provided he doesn't get randomly killed).
Apart from that, all Illyasviel, Nero Claudius (Caster), Sakata Kintoki, Medea, Meltryllis...any of them will do as well provided enough protection has been stripped from First Hassan.
For those using Order Change, in many cases, the 2nd and 3rd slotted Servants will probably live all the way to the end. Be ready to bestow offensive buff when the Order Change Servants comes back to unleash oodles of damage in a 3-turn window. (Fingers crossed he doesn't evade).

Pre-Release Guide

There is but one main strategy most Masters can employ of which multiple variations are possible.
All that is required is to throw Servants, Guts, Hard Survival, and Irish Canine-based Servants at First Hassan long enough for his Special Defense buffs to be worn down.
Once he is vulnerable, he will perish very quickly, a single DPS Servants is all that is technically required, with the rest of the team entirely dedicated to keeping First Hassan busy long enough.
There are three main stategies:

Order Change one DPS with (fed with turn 1 buffs) Divine Three-Legged Race to the sixth slot and stall for as long as possible and hope that by the time the DPS is back, First Hassan is vulnerable and can be killed in 2-3 turns.
Instead of Order Change, keep that DPS in the main team in either slot 2 or 3 and slowly wail on First Hassan - a more gradual approach.
The Super-Sustain Team: Using (NP-Upgraded) Supports such as Merlin and Jeanne d'Arc with the likes of BB to sustain throughout the complete fight and grind First Hassan down.

Generally, a mixture of either option 1 and 3, and option 2 and 3 is used where (a) support(s) keep(s) a tank Servant alive for as long as possible.
Thus, the main Servant to field are Servants with extreme damage protection such as all Cu Chulainn Servants (especially those with Guts), Guts-based Servants such as Nero Claudius and Heracles (especially with Bond CE).
In addition, High Death Resistance is helpful for a strategy 3 approach and BB and First Hassan are great options to try and keep alive as they will not be as easily instantly killed.
Supports with extensive protections especially with Invincibility/Evasion/Defenses are great as well as they can help to buy a lot of time especially for tanking and recuperating from First Hassan's NP. Jeanne d'Arc, Merlin, Mash, etc. can all buy valuable time.
Guts Support is also very useful to keep Servants alive, especially against First Hassan's Instant Death on NP. Irisviel, Nero Claudius (Caster) and Paracelsus are some darkhorse options for this approach.
The normal (Taunt) tanking Servants such as Chevalier d'Eon and Georgios are also pretty decent at holding off First Hassan.
Lastly, Defensive CEs are very powerful. For Servants with no Guts, a Guts CE is highly recommend (doesn't matter which one, but Necromancy is too RNG-heavy and prevents guts skills), while Servants with a Guts ought to go for CEs like Volumen Hydrogen.
For full-sustain tanking, The Holy Shroud of Magdalene is very powerful to be able to live through First Hassan's normal damage.
The Craft Essence - Mature Gentleman is the only Craft Essence in the game that currently grants Instant Death Resistance. Equipping this on the Servant in the First Slot is a decent way to improve their survivability - but puts that Servant at risk of dying from First Hassan's normal damage.

Picking a Damage-dealer

Ideally, only a single Main DPS is needed.
A Single Target Caster would generally be the best option thanks to the class advantage, but Berserker and Alter Ego Servants are more than capable as well.
Sanzang can really pull her weight here, being capable of launching her NP twice in succession to try and finish the final stretch in 2 turns. She is extremely compatible with an Order Change strategy.
Cu Chulainn (Alter) is also great, especially as he can stay on the field and tank additional First Hassan hits (provided he doesn't get randomly killed).
Apart from that, all Illyasviel, Nero Claudius (Caster), Sakata Kintoki, Medea, Meltryllis...any of them will do as well provided enough protection has been stripped from First Hassan.
For those using Order Change, in many cases, the 2nd and 3rd slotted Servants will probably live all the way to the end. Be ready to bestow offensive buff when the Order Change Servants comes back to unleash oodles of damage in a 3-turn window. (Fingers crossed he doesn't evade).

Soloable for New Masters?

Alas, if only. This quest cannot be soloed, especially in its current iteration where even hardened Masters will struggle to deal with all the random elements.

That said, it is possible to feed tank Servants long enough for a borrowed main DPS Servant to finish the job. But that obviously would require a fair amount of investment in having those Servants leveled.
A composition with Cu Chulainn, Cu Chulainn (Caster), Cu Chulainn (Alter) into Hassan of the Cursed Arm, Blackbeard and Leonidas could work alongside all kinds of CEs that grants guts and other protection.
But it would still be heavily RNG-dependent due to First Hassan's basic attacks unto the team.

Video Links

Note that these videos are not affiliated with GamePress, but showcase some lineups that are effective in clearing the final challenge. These can serve as a good reference for how to rotate skills during this quest or simply to have a look at the encounter before diving in.
These videos are all from other servers and do not display the added challenge of dealing with randomized Target Focus debuffs. Nonetheless, they still display all the other elements of the fight in full.

Quick Servant Suggestions

Servants by Instant Death Rate

Main DPS

Additional Order Change Options

First Hassan Tank Fodder

Main Supports

Low Death Rate Servants

Servants with Multiple Guts

Defensive Supports

Guts Supports

CE Recommendations